New study shows that chimpanzees of all ages and all sexes can learn rock-paper-scissors

Chimps of all ages and genders can learn the circular relationship used in rock-paper-scissors, a new study has shown.

The study, Learning the rules of the rock–paper–scissors game: chimpanzees versus children., was carried out by Jie Gao of Kyoto University in Japan and Peking University in China, lead author.

Gao's team wanted to see whether chimpanzees and children had comparable abilities to learn the game, and by doing so see whether chimps could understand extended patterns.

Because the relationship between the game's three signals is non-linear, learning such patterns requires enhanced metnal capacity.

The team used seven chimps of different ages and sexes living in the Primate Research Institute at Kyoto University as part of the experiment. The chimps sat in a booth housing computer-based touchscreens, and they were trained to pick the stronger of two options they saw on screen.

The chimps first learned the paper-rock sequence then the rock-scissors one, then the scissors-paper one. Once they understood these pairs, they were shown all of the different pairs randomly presented to them on screen. Five of the seven chimps completed the training after an average of 307 sessions.

The tea also taught the game to 38 preschool children. The children grasped the game within, on average, five sessions.

Gao said: '"This suggests that children acquire the ability to learn a circular relationship and to solve a transverse patterning problem around the age of four years.

'The chimpanzees' performance during the mixed-pair sessions was similar to that of four-year-old children.'